Psychology and the problem of scientific knowledge

To understand the role of cognitive functions assessment in psychology, we are going to refer to its historical background. However, let's not start with the detailed examination of the history of psychological assessment as it is commonly done in books on experimental psychology, but rather set an eye on the origins of scientific knowledge in general. It is worth to do because of a curious observation that the different branches of science pass through the similar stages in course of their evolution. Applying this theory to psychology, we may find that this science is currently passing through the exceptionally important stage, connected with the practice of psychological assessment. The recent theoretical advances and the growing incorporation of computer technologies make this subject even more promising for the future.

The origins of the modern science as we know it today go back to antique philosophers, who are known for being utterly broad in their studies. This broadness had been probably caused by the difficulties with the division of nature into specific research fields under the lack of factual information. Due to the same reasons, the main method of scientific research was the invention of models for the real world and its component parts. Most of these models were extremely difficult or even impossible to validate with the use of contemporarily available tools and methods. In the course of time, however, as the methods to study the surrounding world and its properties were evolving, the specific sciences had been extracting from the body of the ancient natural philosophy.

For example, let's see how the described scheme worked for chemistry. This science roots in early ages' alchemy. Alchemists used to ground the theoretically deduced models of the surrounding substances on the fatally incomplete experimental data, which predictably led the models to have more fantastic then realistic content (see figure 1 for the scheme of seven chemical elements according to the ancient Egyptian alchemists)1. The situation desired much changes to happen until scientific and technical skills progressed enough to make the research of the atomic properties possible. Once it happened, it didn't take long for a new model, capable to systemize the elements in a logical way to be invented. The system, known as a periodic table by D.I. Mendeleyev had put a solid foundation for chemistry and permitted the further advances due to prediction of other elements, their properties and chemical laws. In such a way, an intensive involvement of the experiment helped to achieve fundamental advance in chemistry.

Turning back to psychology, we notice that this science has only gained its experimental background quite recently, especially in comparison to other sciences. In fact, the body of psychology was historically built upon the same theoretical deduction based on subjective guesses as the ancient alchemy. The definitive book by Aristotle, who is considered to be a father for psychology is called "On the Soul", and this is a general reflection of how psychological research field used to be understood for dramatically too long. Figure 2 shows Aristotelian theoretical scheme of perception, which stayed at the hypothetical level, because it was impossible for people to carry out experiments to prove or deny it. Thus while the legacy of natural philosophy still influences the psychological science, it is extremely important to bring the main concepts and theoretical models to the validating experimental basis.

The experimental approach in psychology has certain differences in comparison with the other sciences, which is probably caused by the peculiarity of the subject of investigation. In the most general view, psychology is considered as a science...

One interesting definition is by Boring (1923) "Intelligence is what is measured by intelligence tests", or I would say what they try to measure. The subject measured by intelligence tests is a big part of what is measured by cognitive functions tests.

The attempts to perform different kinds of psychological testing indicate that certain tasks exist that the psychological testing becomes an instrument to solve them. This section describes the main contemporary applications of the psychological testing.